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Questions and Answers
Which of the following can contribute to the antigenic changes of Influenza A Viruses?
Which of the following can contribute to the antigenic changes of Influenza A Viruses?
What is the term used to describe the gradual accumulation of mutations that allow the virus to escape neutralizing antibodies?
What is the term used to describe the gradual accumulation of mutations that allow the virus to escape neutralizing antibodies?
Which strains of Influenza A Viruses are thought to have changes in three or more antigenic sites?
Which strains of Influenza A Viruses are thought to have changes in three or more antigenic sites?
What can result in antigenic differences in Influenza A Viruses, when it comes to antigenic drift?
What can result in antigenic differences in Influenza A Viruses, when it comes to antigenic drift?
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Which protein can be involved in antigenic changes of Influenza A Viruses?
Which protein can be involved in antigenic changes of Influenza A Viruses?
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How frequently can antigenic drift occur?
How frequently can antigenic drift occur?
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What is required when new HA types are created frequently in Influenza A Viruses?
What is required when new HA types are created frequently in Influenza A Viruses?
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Which of the following is NOT a factor contributing to antigenic changes in Influenza A Viruses?
Which of the following is NOT a factor contributing to antigenic changes in Influenza A Viruses?
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What can antigenic changes of Influenza A Viruses eventually lead to?
What can antigenic changes of Influenza A Viruses eventually lead to?
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Which type of virus is Influenza?
Which type of virus is Influenza?
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What undergoes antigenic shifts and antigenic drifts with the hemagglutinin and neuraminidase proteins?
What undergoes antigenic shifts and antigenic drifts with the hemagglutinin and neuraminidase proteins?
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Which virus is a major cause of life-threatening lower respiratory disease in children?
Which virus is a major cause of life-threatening lower respiratory disease in children?
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Which virus is a major cause of the common cold?
Which virus is a major cause of the common cold?
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Which type of influenza virus undergoes antigenic shifts and drifts?
Which type of influenza virus undergoes antigenic shifts and drifts?
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What is the result of antigenic shifts in influenza viruses?
What is the result of antigenic shifts in influenza viruses?
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What is the result of antigenic drifts in influenza viruses?
What is the result of antigenic drifts in influenza viruses?
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What is the primary site of virus replication in mild influenza?
What is the primary site of virus replication in mild influenza?
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What is the primary site of virus replication in severe influenza?
What is the primary site of virus replication in severe influenza?
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Which type of influenza virus exclusively infects humans?
Which type of influenza virus exclusively infects humans?
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Which type of influenza virus undergoes antigenic drift only?
Which type of influenza virus undergoes antigenic drift only?
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What causes influenza A pandemics?
What causes influenza A pandemics?
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What causes epidemics of influenza A and B?
What causes epidemics of influenza A and B?
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Which animals are the natural reservoirs of all subtypes of Influenza A viruses?
Which animals are the natural reservoirs of all subtypes of Influenza A viruses?
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What is the gold standard for the diagnosis of influenza?
What is the gold standard for the diagnosis of influenza?
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Which type of influenza virus is responsible for causing pandemics?
Which type of influenza virus is responsible for causing pandemics?
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Why do we not have influenza B pandemics?
Why do we not have influenza B pandemics?
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What is the primary site of virus replication in mild influenza?
What is the primary site of virus replication in mild influenza?
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What is the term used to describe the gradual accumulation of mutations that allow the virus to escape neutralizing antibodies?
What is the term used to describe the gradual accumulation of mutations that allow the virus to escape neutralizing antibodies?
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What is the result of antigenic shifts in influenza viruses?
What is the result of antigenic shifts in influenza viruses?
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Which of the following is a major antigenic change of Influenza A viruses?
Which of the following is a major antigenic change of Influenza A viruses?
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Antigenic shifts of Influenza A viruses occurs by?
Antigenic shifts of Influenza A viruses occurs by?
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Which type of vaccine is grown in embryonated eggs and is 70-90% effective in healthy persons?
Which type of vaccine is grown in embryonated eggs and is 70-90% effective in healthy persons?
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Which type of vaccine is widely used in Russia but not elsewhere?
Which type of vaccine is widely used in Russia but not elsewhere?
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What is the basis of today's influenza vaccines?
What is the basis of today's influenza vaccines?
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Which antiviral drug blocks the M2 ion channel and is effective against Type A influenza virus if given early?
Which antiviral drug blocks the M2 ion channel and is effective against Type A influenza virus if given early?
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Which antiviral drug is a neuraminidase inhibitor and is effective against both Type A and Type B influenza viruses if given early?
Which antiviral drug is a neuraminidase inhibitor and is effective against both Type A and Type B influenza viruses if given early?
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What is the focus of current research for a universal vaccine against influenza?
What is the focus of current research for a universal vaccine against influenza?
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Which family does Parainfluenza viruses belong to?
Which family does Parainfluenza viruses belong to?
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What is the size of Parainfluenza viruses?
What is the size of Parainfluenza viruses?
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How many serotypes of Parainfluenza viruses are there?
How many serotypes of Parainfluenza viruses are there?
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What is the genome of Parainfluenza viruses?
What is the genome of Parainfluenza viruses?
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When do Parainfluenza 1 and 2 infections occur?
When do Parainfluenza 1 and 2 infections occur?
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What is the most common clinical symptom of Parainfluenza 1 and 2 infections?
What is the most common clinical symptom of Parainfluenza 1 and 2 infections?
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What is the most common clinical symptom of Parainfluenza 3 infection?
What is the most common clinical symptom of Parainfluenza 3 infection?
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What is the primary site of Parainfluenza virus replication?
What is the primary site of Parainfluenza virus replication?
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What type of antibodies show a good correlation with protection against Parainfluenza virus infection?
What type of antibodies show a good correlation with protection against Parainfluenza virus infection?
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Is there currently a vaccine available for Parainfluenza viruses?
Is there currently a vaccine available for Parainfluenza viruses?
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Which age group is most likely to be seropositive for Parainfluenza type 3?
Which age group is most likely to be seropositive for Parainfluenza type 3?
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How is Parainfluenza virus transmission initiated?
How is Parainfluenza virus transmission initiated?
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What type of infection occurs in Parainfluenza virus transmission?
What type of infection occurs in Parainfluenza virus transmission?
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Which virus is the primary cause of lower respiratory tract illness in young children?
Which virus is the primary cause of lower respiratory tract illness in young children?
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What is the family of Respiratory Syncytial Virus (RSV)?
What is the family of Respiratory Syncytial Virus (RSV)?
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What is the size of Respiratory Syncytial Virus (RSV)?
What is the size of Respiratory Syncytial Virus (RSV)?
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How many serotypes of Respiratory Syncytial Virus (RSV) are there?
How many serotypes of Respiratory Syncytial Virus (RSV) are there?
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How is Respiratory Syncytial Virus (RSV) transmitted?
How is Respiratory Syncytial Virus (RSV) transmitted?
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Which age group is most likely to be seropositive for Respiratory Syncytial Virus (RSV)?
Which age group is most likely to be seropositive for Respiratory Syncytial Virus (RSV)?
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What is the primary site of Respiratory Syncytial Virus (RSV) infection in childhood?
What is the primary site of Respiratory Syncytial Virus (RSV) infection in childhood?
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What is the most common clinical symptom of Respiratory Syncytial Virus (RSV) infection in childhood?
What is the most common clinical symptom of Respiratory Syncytial Virus (RSV) infection in childhood?
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What type of infection occurs in adult Respiratory Syncytial Virus (RSV) infection?
What type of infection occurs in adult Respiratory Syncytial Virus (RSV) infection?
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When does the RSV season typically occur in northern climates?
When does the RSV season typically occur in northern climates?
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Which of the following is a risk factor for Respiratory Syncytial Virus (RSV) infection?
Which of the following is a risk factor for Respiratory Syncytial Virus (RSV) infection?
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How does RSV enter the body?
How does RSV enter the body?
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Which of the following is a symptom of RSV infection in children?
Which of the following is a symptom of RSV infection in children?
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Which of the following is NOT a factor contributing to increased risk of RSV?
Which of the following is NOT a factor contributing to increased risk of RSV?
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Which type of genome does Respiratory Syncytial Virus (RSV) have?
Which type of genome does Respiratory Syncytial Virus (RSV) have?
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What is the family of Respiratory Syncytial Virus (RSV)?
What is the family of Respiratory Syncytial Virus (RSV)?
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Which family does the Rhinovirus belong to?
Which family does the Rhinovirus belong to?
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What is the size of the Rhinovirus?
What is the size of the Rhinovirus?
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What are the two unique physical properties of the Rhinovirus?
What are the two unique physical properties of the Rhinovirus?
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At what temperature does the Rhinovirus replicate better?
At what temperature does the Rhinovirus replicate better?
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How do Rhinoviruses compare to other enteroviruses in terms of pH stability?
How do Rhinoviruses compare to other enteroviruses in terms of pH stability?
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Which type of genome does Rhinovirus have?
Which type of genome does Rhinovirus have?
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What is the primary site of Rhinovirus infection?
What is the primary site of Rhinovirus infection?
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Which of the following viruses is destroyed at low pH?
Which of the following viruses is destroyed at low pH?
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Which receptor does the Rhinovirus attach to in the nasal passages?
Which receptor does the Rhinovirus attach to in the nasal passages?
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What is the primary site of Rhinovirus infection?
What is the primary site of Rhinovirus infection?
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How does the Rhinovirus primarily spread? MAJOR SOURCE OF TRANSMISSION
How does the Rhinovirus primarily spread? MAJOR SOURCE OF TRANSMISSION
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Study Notes
Influenza A Viruses
- Antigenic changes are influenced by genetic mutations, reassortment, and environmental factors.
- The term for the gradual accumulation of mutations that enable the virus to evade neutralizing antibodies is "antigenic drift."
- Strains with changes in three or more antigenic sites often include H1N1, H2N2, and H3N2.
- Antigenic drift causes variations in influenza A viruses due to frequent mutations in the hemagglutinin (HA) and neuraminidase (NA) proteins.
- Antigenic change can involve the HA and NA proteins which are critical for the virus's ability to infect hosts.
- Antigenic drift can occur frequently, generally every 1–2 years.
- New HA types require updated vaccines and public health strategies to manage increased transmission risks.
- Environmental factors, such as climate and viral strains, do not contribute to antigenic changes.
- Antigenic changes can ultimately lead to influenza pandemics and shifts in predominant viral strains.
- Influenza is an RNA virus belonging to the Orthomyxoviridae family.
- Antigenic shifts and drifts occur mainly in the HA and NA proteins of influenza A viruses.
- Respiratory Syncytial Virus (RSV) is a major cause of life-threatening lower respiratory disease in young children.
- Rhinovirus is the primary cause of the common cold.
- Antigenic shifts can result in new pandemic strains, while antigenic drifts lead to seasonal outbreaks.
- In mild influenza cases, the primary site of virus replication is the upper respiratory tract; in severe cases, it is the lower respiratory tract.
- Human infections are primarily caused by influenza B viruses, which do not undergo pandemics.
- Natural reservoirs for all subtypes of Influenza A viruses include aquatic birds.
- The gold standard for diagnosing influenza is the reverse transcription PCR (RT-PCR).
- Influenza A viruses are responsible for pandemics while Influenza B viruses contribute to seasonal epidemics.
Vaccines and Antivirals
- The egg-based vaccine for influenza is 70-90% effective in healthy individuals.
- Live attenuated vaccines are commonly used in Russia but less so in other regions.
- Current influenza vaccines are based on circulating viral strains.
- Adamantanes, such as Amantadine, block the M2 ion channel affecting type A influenza.
- Neuraminidase inhibitors, like Oseltamivir, are effective against both A and B types if administered early.
- Research is ongoing for a universal flu vaccine targeting conserved viral proteins.
Parainfluenza Viruses
- Parainfluenza viruses belong to the Paramyxoviridae family and are relatively small in size.
- There are four serotypes of Parainfluenza viruses, characterized by RNA genomes.
- Infections with Parainfluenza types 1 and 2 usually occur in the fall.
- The most common clinical symptoms for Parainfluenza types 1 and 2 include croup, while Parainfluenza type 3 primarily presents with bronchiolitis.
- The primary replication site for Parainfluenza viruses is the upper respiratory tract.
- Antibodies, particularly IgG and IgA, are correlated with protection against Parainfluenza virus infections.
- Currently, no vaccine is available for Parainfluenza viruses, with parental immunity being crucial.
- Infants are most likely to be seropositive for Parainfluenza type 3, and transmission occurs via respiratory droplets.
Respiratory Syncytial Virus (RSV)
- RSV is part of the Paramyxoviridae family and is comparable in size to Parainfluenza viruses.
- There are two serotypes of RSV, known as A and B.
- RSV is primarily transmitted through direct contact with respiratory secretions.
- The highest seroprevalence for RSV is seen in children under two years of age.
- In young children, RSV primarily infects the lower respiratory tract, leading to symptoms like wheezing and cough.
- RSV infections can be severe in infants, reflecting in higher hospitalization rates.
- The RSV season typically peaks in fall and winter in northern climates.
- Major risk factors for RSV infection include prematurity, congenital heart disease, and exposure to secondhand smoke.
- RSV enters the body through the respiratory tract, establishing infections in the nasopharynx.
Rhinovirus
- Rhinoviruses belong to the Picornaviridae family and are small, non-enveloped viruses.
- They are stable only at certain pH levels, typically better replicating at a higher temperature around 33°C.
- Rhinoviruses show lower stability at a low pH compared to enteroviruses.
- Rhinovirus has a single-stranded RNA genome and primarily infects the upper respiratory tract.
- Rhinovirus attaches to intercellular adhesion molecule-1 (ICAM-1) in the nasal passages.
- Rhinoviruses spread mainly through respiratory droplets and direct contact with contaminated surfaces.
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Description
Test your knowledge on respiratory viruses with this quiz! Learn about the major causes of lower respiratory disease in children, including Influenza, Parainfluenza virus, Respiratory Syncytial Virus (RSV), Rhinovirus, Coronavirus, and Adenovirus. Gain a general background on influenza viruses as well. Challenge yourself and expand your understanding of these infectious agents!